81146551 has 8 divisors (see below), whose sum is σ = 83611440. Its totient is φ = 78716352.

The previous prime is 81146537. The next prime is 81146563. The reversal of 81146551 is 15564118.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81146551 - 2⁵ = 81146519 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81146501) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3885 + ... + 13318.

It is an arithmetic number, because the mean of its divisors is an integer number (10451430).

Almost surely, 2^81146551 is an apocalyptic number.

81146551 is a deficient number, since it is larger than the sum of its proper divisors (2464889).

81146551 is a wasteful number, since it uses less digits than its factorization.

81146551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17345.

The product of its digits is 4800, while the sum is 31.

The square root of 81146551 is about 9008.1380429032. The cubic root of 81146551 is about 432.9356559980.

The spelling of 81146551 in words is "eighty-one million, one hundred forty-six thousand, five hundred fifty-one".